Ihave a new ram 15oo limited took it to a moble 1 express oil change @2100 miles at Cedar Hill Tx. I ask for mobile 1 5w-30wt. They refused to change it to that wt. Said company management said they have to by what the oil cap said..I paid cash for this truck and I will put whatever I want in it. I LEFT WITH THE HEMI ACCIDENTLY TIRES SQUEALING.I am 80 served in war been shot at now their telling me what oil wt. Ihave to use in my vehicle B S Iwill do it myself.